Adolescent and young adult (AYA) hematopoietic stem cell transplantation (HSCT) patients face a variety of well-documented physical and emotional challenges. In addition to undergoing a life-threatening procedure that involves an intense treatment regimen and lengthy hospital stay, these patients face a protracted 12-month recovery period marked by numerous physical, emotional and psychosocial challenges, such as coping with immunosupression and its socially isolating effects; fatigue, adherence to complex medication regimens; and meeting hydration and nutrition requirements. Failure to meet these challenges not only engenders distress, anxiety and depression, but can also result in serious consequences to health such as organ damage and/or chronic, severe graft versus host disease. Unfortunately, in reality, it is not uncommon that HSCT patients often fail to meet these challenges or behavioral requirements. This is especially true for AYAs, whose developing autonomy and enjoyment of peers is often juxtaposed with the constraints of cancer treatment. Interventions that assist recipients in successfully completing the requirements of HSCT recovery are needed to maximize physical and psychological health outcomes. The proposed Phase I study will evaluate the feasibility and patient acceptance of an internet-based, interactive and personalized intervention to promote self-management behaviors among AYA allogeneic HSCT recipients during their extended outpatient recovery period. We will utilize an innovative approach that directly links behavioral objectives to game mechanics within the intervention. The intervention will address constructs key to motivation and adherence such as barriers, resiliency, social support, and positive reinforcement. By completing structured real world behavioral tasks on an appropriate schedule, participants will earn points, virtual achievements, items, gifts and bonuses that will be utilized to advance through an online game environment. The intervention will offer a set of relevant social network features, including mechanisms for patient-to-patient communication, competition, and collaborative problem solving. The overall goal is to maximize positive psychological and physical health outcomes. Phase I study participants include 30 AYA allogeneic HSCT patients age 15-29 years from MD Anderson. We will conduct focus groups and informal, iterative usability analysis with 8 HSCT survivors during the prototype intervention development process. Upon completion of prototype construction, we will conduct acceptance evaluation of the proposed system with 22 participants who are within their first year of post-transplant outpatient care. We will measure system performance, user perceptions of the program, intention to use the system, and actual system usage over a 3-week period. The proposed study will further scientific knowledge on the impact of game mechanics and social networking on behavior, and will provide insights, evidence, and guidance on how to build practical online social intervention systems to support behavioral change.